
TURNING AND 
BORING TAPERS 




BY FRED H. COLVIN 



BEING 
NUMBER^ ^ ' ; 




OF A 
SERIES OF 

PRACTICAL 
PAPERS 

PUBLISHED BY 






NEW YORK 





'\ 



^*^ 







LIBRARY of CONGRESS 
Two Copies Received 

DEC 24 1903 

Copyright Entry 



H 




Turning and Boring Tapers 

The problem of turning tapers — or more properly 
the taper wanted — is often puzzling, and ''rules" are 
frequently asked for. 'As is often the case, a clear 
understanding of the question is much better than a 
rule, for this might easily be applied in the wrong way. 

Tapers are designated either by the amount per 
inch or per foot or the number of degrees of the angle 
made by the sides and the center line or between the 
sides. This latter sometimes causes confusion, as will 
be seen later, but each method will be carefully ex- 
plained. 




Derry CoUard Co I 
Figure i. Showing taper at various points. 

When they are designated by the amount per foot, 
the usual way, the difference in diameters is always 
meant as in pipe thread tapers or in taper ke3^s. Thus, 
pipe threads taper % of an inch to every foot in length 
or I inch in i6 inches. This means a pipe tap with 
this taper and one foot long would be 3^ of an inch 
larger at one end than the other or that the diameter 
would increase -^^ of an inch to every inch in length, 
as shown in figure i. 



Copyright 1902 by The Derry-Collard Co, 



Turning and Boring Tapers. 

To avoid confusion, the drawings or instructions 
should say plainly whether the angle mentioned is 
between the center line of the bar or between the 
sides, the former being just half the latter, as seen in 
figures 2 and 3. 

In thinking of the angles it is simpler to think of 
the sides (or the total or. included angle), as the center 
line is an imaginary affair at best, but when using a 




Figure 2. Angles each side of center line. 

compound rest on a lathe we run against the center 
line unless we are careful. This will be shown in the 
section under compound rests. 

Turning tapers between centers being the method 
usually inquired about, will be first considered. In 
all the views shown we are looking down on the lathe. 




Derry CoUard Co 



Figure 3. Total angle. 

With both the live spindle and the tail stock or 
dead spindle in line and centers true, a piece of work 
will be straight or of equal diameter at both ends — a 
condition unfortunately that is not as easy to obtain as 
might be imagined. 



Turning and Boring Tapers. 



Remembering that the lathe tool moves with the 
carriage in a line parallel with the lathe centers when 
they are in line, it is easy to see how any variation in the 
position of either center will make the lathe turn 
smaller at one end or the other. The end on the center 
nearest the tool will of course be smaller than the other, 
as indicated by figures 4 and 5. 




Derry CoUurd Co 



Figure 4. Ordinary method of turning tapers. 

With very few exceptions, tapers are turned with 
the small end toward the dead center or tail stock, so 
that the dead center is always moved toward the tool 
or front of the lathe. Should it be necessary to turn a 
taper like figure 5, the dead center must be moved back 
as shown. Tapers of the regular kind will be consid- 
ered, however, in every case, and any movement of the 




Derry CollarJ Co 



Figure 5. Large end at tail stock. 

tail Stock from the center line will be toward the front. 

It may be well to mention here the effect on the 

work if the centers are out of line vertically — that is, 

3 



Turning and Boring Tapers. 



in line back and front, but the live spindle higher or 
lower than the tail stock. 

With the dead center either higher or lower than 
the live center the taper will be less than if they were 
in line. This difference in diameter will not be nearly 
so great as though the centers were out of line the same 
amount sideways or horizontally, but it must be 
guarded against when on especially nice work. 



1/2 to 4 — 11/2 to 1 foot 




Derry CoUard Co 



Figure 6. Taper given a 4-inch piece. 

Suppose we have a piece of metal 4 inches long and 
2 inches in diameter, and can hold this by simply touch- 
ing the centers against the ends, as shown in figures 4, 
5 and 6. If we wdsh to make this taper so as to be i^ 
inches at the small end and still be 2 inches at the large 
end, we move the tail stock over ^ of an inch or half 
the difference between the diameters of the two ends 
of the taper. This is shown in figure 6, and we would 
then have a taper of Y-z an inch in 4 inches, i inch in 8 
inches, or i Y-z inches to the foot, which is the usual way 
of expressing it. 

Now, suppose we put in a piece 8 inches long in- 
stead of 4 inches. The tail stock is set over Y\ inch so 
that the small end must still be Y'^ an inch smaller in dia- 
meter than the large end, leaving it i Y'^ inches as before. 



Turning and Boring Tapers. 



But the taper is now ^ inch in 8 inches or 3^ inch to the 
foot, only one-half as great as before. This is shown 
in figure 7, and shows very plainly that the taper cut 
by the lathe depends on the length of the piece and 
amount of offset given the tail stock. To a slight 
extent it also depends on the hight of the cutting 
point of lathe tool, which should be at the center. If 
this cutting point is either above or below the center 
the taper will be slightly less, as the cutting point is 
then a trifle farther from the dead center. This does 
not affect it to any great extent, however, but should 
be noted. 

Continuing on the basis that the centers bear 
against the ends of the piece to be turned, which is not 
practical, but makes it easier to calculate, we come to 
the problem of finding how much to set the tail stock 
over to turn a given taper on a piece of a certain 
length. 

In practice the tapers turned are usually on the 
end of a bar, and it should be remembered that the 

Vz to 8 - /^ to 1 foot 

Pipe tap taper 




Derry Collard Co 
Figure 7. Taper on 8-inch piece — same offset. 

length of the taper is of no consequence, as far as set- 
ting the lathe is concerned, but only the amount of 
taper and the length of piece to be turned. If you 
want a taper portion 3 inches long on the end of a bar 
that is 18 inches in length, and the taper is to be i inch 



Turning and Boring Tapers. 

to the foot, the tail stock must be set over one-half the 
amount of taper per foot for every foot of length of the 
bar. As the bar is i^ feet long, the tail stock must 
come over i Y-z times ^ inch, or 3^ of an inch. 

We can either reduce the taper to the amount per 
inch and then multiply this by ^ the length of the bar 
in inches, or find the taper for the entire length and 
then move the tail stock over one-half of this. The 
latter is the easiest, as we shall see from the following 
example: Bar is 39 inches long, 2 inches in diameter. 
Taper of ^ inch to foot wanted at one end, and the 
small end must be 1 3^ inches when finished. How far 
must tail stock be set over and how long will taper be? 
One-half inch to foot is -gV of an inch to each inch in 
length, and 39 inches times -^ or -||- or ijf or i^ 
inches in the length of bar. Then tail stock must be 
set over one-half of i^. As i^ equals -g-, one-half of 
this is yf of an inch. Or we can call 39 inches 3%' feet, 
and we find that total taper is 3^ times'^, or i^ 
inches as before. 

As the taper is }^ inch to foot and the small end 
must be I % inches, or y^ inch less than the original, it 
is evident that the taper will be 6 inches long, as the 
reduction in diameter is just half the taper per foot. 

Another way of determining the offset for the tail 
stock when there is a taper to be turned on the end of 
a long piece is as follows : Suppose the bar is two feet 
long and you want a taper 6 inches long. The large 
end of taper is 3 inches and the small end 2 inches. 

Divide the difference between the large and small 
ends by 2, that is, 3 minus 2=1 and divided by 2 gives 
Yz. If the taper was the whole length of bar this 
would be the offset. 



Turning and Boring Tapers. 



As it extends only one-quarter the length of the 

bar, the offset will be 4 times ^ inch, or 2 inches. 

This makes the rule as follows : 

" Subtract small diameter of taper from large end 

and divide this by two. Multiply this by the length of 

the bar and divide by length of taper. Or, divide 

length of bar by length of taper (both in inches) and 

multiply the offset first found by this amount." 

Those who like formulas might prefer this : — 

/.= length of bar. 

/ = " " taper. 

Z)=:large diameter of taper. 

^=small " 

L D — d 
Then the offset equals -^ X — ;; — , or in this case 

24 3 — 2 

-— X — - — = 2 inches offset, 
u 2 



/ 




Figure 8. Action of work on centers. 

Having seen how tapers are made under the imag- 
inary conditions named, we must now consider the prac- 
tical questions involved, the most serious being the fact 
that the centers must enter a sufficient distance to sup- 



Turning and Boring Tapers. 



port the work, and that the work is carried in a cramped 
and constantly changing position owing to the offset, as 
shown in figure 8. 

It will be seen that the effective length of the bar, 
so far as our calculation is concerned, has been short- 
ened by the depth of the center on each end, and the 
depth of both must be deducted if we wish to get down 
as fine as possible. The longer the piece or bar, the 



less 



each center is li inch 




Derry Uollard Co 



Figure 9. Taper bearing at ends only. 



deep, the effective length of bar is only reduced from 
24 to 23)4 inches — a change of nearly y|„- of an inch to 
the foot ; and the careful man will want to know why 
the taper is not exactly as calculated. 

As a matter of fact, it is not wise to depend too 
much on calculations in this case, as at best they are 
only a guide, and the practical man measures very care- 
fully with a gage, if he has one, or with calipers at two 
points a measured distance apart. The calculations are 
useful in getting pretty near the right taper, but it is 
safer to measure after each cut and adjust the tail stock 
accordingly. In fact, turning a taper just right or two 
just alike in an ordinary lathe is not always easy to do. 



Turning and Boring Tapers. 

Where it is not necessary to have a fit the whole 
length of the taper it is a rather common practice to 
relieve the taper in the center of either piece, as it is 
much easier to obtain a g^ood fit, free from shake, than 
when taper extends the whole length. This is shown 
in figure 9. 

In the foregoing, tapers have been considered as a 
given amount to the foot, as is usually the case when 
turned by moving tail stock. When tapers are desig- 
nated in degrees, the angle is usually obtained by the 
compound rest, but for the convenience of those who 
v/ish to compare the two, the following table has been 
prepared : 



Equivalent 


Tapers of Degrees in Inches. 


Total number of degrees 


Total taper per inch in 


Total taper per foot in 


included in angle. 


inches. 


inches. 


1 


.01746 


.20952 


2 


.03490 


.41880 


3 


.05236 


.62832 


4 


.07984 


.95808 


5 


.08732 


1.04784 


7% 


.13108 


1.57296 


10 


.17498 


2.09976 


15 


.28330 


3.15960 


20 


.35266 


4 23192 


25 


.44338 


5.32056 


30 


.53590 


6.43080 


35 


.63060 


7.56720 


40 


.72794 


8.73538 


45 


.82842 


9.94104 


50 


.93262 


11.19144 


55 


1.04114 


12.49368 


60 


1.15470 


13.85640 



Tapers with Compound Rest. 

The compound rest is an attachment between the 
lathe carriage and the tool post, capable of being swung 
around to any angle and having an independent feed 
screw so that the tool can be fed by this independent 
screw at the angle desired. The base of the compound 
rest is indexed or divided into degrees so as to be con- 




TO. ** Squaring off" with 
compound rest. 



Derry Collard Co 




veniently set. This makes it very easy to set the rest 
so as to cut the desired angle after you know what it is, 
but as there is often confusion on this score it is best to 
set it straight before we commence. 

With the centers in line as for straight turning, 
compound rest "square" or at right angle to the 
"shears" or 'Svays" of the lathe, it will face off a piece 
so that the end will be 90 degrees from either the out- 
side or an imaginary line running between centers, but 
the "included angle," or the angle from one side of the 



10 



Turning and Boring Tapers. 



part just cut to the other, as shown in figure lo, will 
be twice 90, or 180 degrees. 

Compound rests are differently arranged by the 
various makers, and the manner of graduating them 
might tend to confuse if we do not thoroughly under- 
stand in the beginning. In some the graduations are 
on the back, some on the front, but they are mostly on 
the side. 

A very common way — and a good one — is to gradu- 
ate each w^ay from a center line, and as 90 degrees or 
quarter of a circle is generally used, this gives 45 de- 
grees on each side. With a mark on the lower or 
stationary part at each end of the divisions, it is easy 
to turn to any desired angle with the lathe centers. 
This is shown in figure 11. 




Derry CoUard Co 

Figure 1 1 . A common method of graduation. 

If the graduation is as indicated in figure 12, you 
can only measure 45 degrees in either direction or 90 
degrees in all. By increasing this to 60 degrees and 
putting additional marks at 30 degrees each side of 
these, 180 degrees can be obtained as with the first 



II 



Turning and Boring i apers. 

g-raduation shown. But in any case, if you remember 
that it is the number of degrees ''out of center" or 
away from normal position that counts, there will be 
no trouble. 

Now, if we move the compound rest out of center 
15 degrees, as shown in figure 13, we shall make a cut 
which is 15 degrees away from the square facing-off 
movement of carriage, 75 degrees from the center line 
and 150 degrees of included angle, as shown. This is 
what fools many a man who is not used to angles or a 
compound rest, for having moved the rest 1 5 degrees, 
he never thinks but that he will get a 1 5 degree angle. 




Deny CoUai il Co 



Figure 12. Another method 

He will if he measures from across the end, but in no 
other way. This shows the necessity for having draw- 
ings plainly marked, so as to show whether the angle 
given is the total or included angle or the angle be- 
tween the center line and the side. The total or in- 
cluded angle is the one generally meant, and will be 
considered. 

12 



Turning and Boring Tapers. 



There is too little care used in expressing angles 
of globe and other valve seats. A 60 degree seat is 
common and means 60 degrees total angle, as it should, 
but in the next breath we speak of a "45 degree seat," 
when it should be a "90 degree seat " instead. 

Setting the compound rest to 30 degrees and we 
have a total angle of 120 degrees, while if it goes to 45 
degrees, it gives a total angle of 90 degrees. 




Figure 13. Compound rest 
moved 1 5 degrees out of center 



Derry CoUard Co 

From this we can make a little rule to the effect 
that " the total angle of the piece turned will equal i8o 
degrees, minus twice the setting of the compound rest 
from the square position," or "subtract the desired 
total angle from i8o degrees and ^ of the remainder 
is the correct setting of the compound rest." 

We wish to turn a valve seat reamer to 60 degrees 
total angle, what is the correct setting of the compound 
rest? 

Then 180 — 60=120, y^ of 120=60, which is the 
correct number of degrees out of center, for setting the 
compound rest? 



Turning and Boring Tapers. 

A reamer is desired, having a total angle of 15 
degrees, what is correct setting of compound rest? 

Then 180 — 15=165, y^ of i65=:82%, or within 7>4 
degrees of being parallel with the lathe centers. A 
little thought wdll show this without the rule, as by 
taking half the degrees in the total angle desired from 
the right angle position of the com_potind rest you get 
the correct angle. 

With the compound rest set 50 out of centre, what 
will be the total angle cut? Twice 50=100, 180 — 
100=80. Total angle cut will be 80. 

In all compound rest turning or boring, as w^ell as 
with taper w^ork of any kind, have cutting point of tool 
at hight of lathe center. 

▼ ▼ V 

Taper Turning Attachments, 

Several makes of lathes have taper turning attach- 
ments to avoid the setting over of tail stock and its 
attendant evils. They are all based on the idea shown 
in figure 14, although this is a rather crude application 
of the principle. The tool block is disconnected from 
the screw and fastened by piece B to a block sliding in 
or on the piece A A, which is moved to any desired 
taper. One end of this is moved the same amount as 
the tail stock would be, or if both ends are moved, the 
total movement out of central position in opposite directions 
must equal half the amount of taper in a piece as long 
as the piece A A. This supposes the graduations to 
be at the end of the bar A A. If they are not, the 
length should be taken at the graduating point. The 

14 



Turning and Boring Tapers, 

length of the piece being turned does not count here, 
but the length of the piece A A or that part of it which 
controls the movement of the tool block. 




Derry Collard Co 



Figure 14. Principle used in taper attachments. 

If the taper bar or piece is 12 inches long, and we 
wish to turn a pipe taper which is ^ inch per foot, 
then it must be set out of center one-half this amount 
or ys of an inch. Others tapers are found in the same 
manner, and if the taper is given in degrees, the 
equivalent taper per inch and per foot can be found 
from the table on page 9. 

T T T 



Taper Boring. 



Taper boring differs from taper turning, as it can- 
not be done by setting over lathe centers unless a 
boring bar is employed, or as shown in figure 16. This 
is only one type of bar, but the idea is the same in all. 
The bar is held stationary between centers which are 



Turning and Boring Tapers. 



set over the correct amount. The boring tool is held 
in a cutter head, which is moved along the bar by the 
screw S. This screw is turned either by hand or by a 
lug fastened on the work, striking a star wheel on the 
screw every revolution and giving the screw a partial 
turn. With this, the tail stock is set over just as though 
the boring bar was the piece to be turned, as in our first 
problem except that the tail stock is m^oved forward 
instead of back. 

The exception to the first statement made in regard 
to boring tapers is in a case similar to that of figure 
1 6, which shows a friction pulley being bored in this 




Derry CoUard Co 



Figure 15. Boring tapers with boring bar. 

way. Where the diameter of the work is large in pro- 
portion to length to be bored and it can be driven on 
an arbor or centerpiece of the work itself, this can be 
done. But in these cases, which are rare, the tail stock 
must be set forward, as shown in figure 5. Where work 
is bolted to face plate or held in a chuck, as is usually 
the case, the taper must be obtained with a compound 
rest or some of the taper attachments. The latter are 
the best in any case, as setting over the tail stock and 
running work at an angle on centers is a barbarous 
proceeding at best. 

16 



Turning and Boring Tapers. 

Turning tapers on brass working lathes is usually 
accomplished by the slide rest, which can be compared 
to the compound rest of the engine lathe, or by using 




v:r^ Uerry Collard Jo 



Figure i6. Boring taper work held on arbor. 

a tool in the tail stock spindle and swinging the tail 
stock around the desired amount. In this latter case^ 
the work is held in screw or other chucks. 

T ▼ ▼ 



Taper Threads. 



The cutting of threads on tapers is sometimes the 
subject of much discussion. Some contend that the 
thread tool should be at right angles to the taper sur- 
face, but it is generally conceded that it is better to 
make the thread at right angles to the center line of the 
taper piece. The difference in the two methods can be 
seen by comparing figures 17 and 18. The taper is 
here very sharp to show the difference more clearly. 

The thread tool can be easily set by taking the 
taper work out of the centers and putting in a straight 

17 



Turning and Boring Tapers. 




Figure 17. Thread tool square with lathe. 

piece of work, such as an arbor or mandrel. Then use 
this to square the tool point by the thread gage and you 




Figure 18. Thread tool square with center line of taper. 
la 



Turning and Boring Tapers. 

have it with almost no trouble, and all guesswork is 
avoided. 

In this connection it may not be amiss to offer a 
suggestion regarding taper fittings for pipes. Standard 
pipe fittings are yq to the inch or 3^ inch to foot, and 
for large pipes this is generally adhered to. 

In small sizes it is common practice to use straight 
taps and taper dies, which has the effect of making the 
joint at the outside of fitting only. 



Calk here 



Calk here 




Makes Tight Joint 
here 



Any kind 
Fitting 



Derry Collard Co 



Figure 19. Suggested method of fitting pipes. 



A method has been proposed which seems to have 
several good points for all sizes of pipe. The plan is to 
use a taper tap, but have the pipe thread straight, so as 
to bring the tearing on the end of pipe. This being 
thin will force into a good contact, and also allow a good 
chance to calk the fitting around the pipe. The latter 
applies especially to large wrought iron fittings. This 
plan is shown in figure 19 as above. 

19 



One Way of Designating Tapers. 



As tapers are sometimes given as i in 2 or i in 4, 
the table below may be of use in reducing them all to 
tapers per foot. The taper in all cases given is the 
total taper between the sides of the piece. 

Taper of 1 in 2=6 inches to the foot 







" 3=4 




<( n 






" 4=3 




a (( 






" 5=2.4 ' 




(( (( 






" 6=2 




(( (( 






" 7=1.71 ' 




(( (( 






" 8=1.5 ' 




I. i I 






" 9=1.33 ' 




it a 






"10=1.2 ' 




'• "■ 






"11=1.09 ' 




IC ki 






"12=1 ' 




n ^l 



V V T 



Morse Tapers. 



H 

e 


t3 
c 
W 

e 

w 

n 
E 

"o 

E 

ni 

5 




w 



T3 
C 

w 

E 
5 


0. 
« 
Q 

p 

C 
CO 


c 
W 

x; 

to 
c 

4> 

— 


x; 
1^ 


a: 

x: 

4) 

Q 







m 
"0 

-r) 
c 


Ofl 

c 


ClJ 


3 

.C 


H 


C 
(U 


.0 

c 




4J 

"5 

e 
5 




aa 
c 

H 

>+-c 



1/5 
4) 

c 

:§ 

H 


to 
c 

H 



§ 



<L) 

C 

'0 

to 

.5 


x: 
u 

ID 

Q 

c 
x: 





1- 

0. 
)_ 
(D 


x: 
u ' 
c 

<D 

a 
0. 



XI 

s 

2 


1 D 


A P 1 B 1 H 1 K 


L 1 W 


T 


d 


t 


R 

-A 

1 

A 

5 

i~6 

3 

8 

1 
2 


a 


S 






1 
2 
3 
4 
5 
6 


.369 

.572 

.778 

1.020 

1.475 

2.116 


.475 

.700 

.938 

1.231 

1.748 

2.494 


2|- 
2x^6 
3A 
4x^ 

7i 


2-A 

3-16 

H 
41 
6 
016 


2-A 

21 
3i 

1-3 
Is 


2x^6 

24 

3xS 

31 

7 


1 

7 

8 
lA 

u 

H 


.213 

.26 

.322 

.478 

.635 

.76 


5 

16 
3 

7 
16 

1 
2 
5 
8 

1 


.35 

17 
32 

1 
31 

32 

Hi- 
2 


41 

1 

-A 

if 
5 

8 

i 


.05 
.06 
.08 
.10 
.12 
.15 


21 
21 
35^6- 

4* 
51 

8 


.600 
.602 
.602 
.623 
.630 
.626 


.050 

.05016 

.05016 

.05191 

.0525 

.05216 


1 


4 
5 
6 



Turning and Boring Tapers. 

It is not deemed advisable to give all the tapers 
per inch in degrees, as few compound rests allow of a 
finer sub-division than half a degree. Instead of this, 
we have selected a number of the degrees in common 
use and given the taper per inch and per foot. From 
this we see that the standard pipe taper of 3^ inch per 








Morse tapers and sockets. 



foot is about 3 ^2 degrees, this being the nearest to it in 
the list. This table is on page 9. 

The table gives the tapers to five decimal places, 
but it is unnecessary to use more than you think is 
needed for the work in hand. Two or three is usually 
all you need. 

21 



Other Tapers. 

Morse Twist Drill Company's standard taper pins 
are made ^ inch to the foot or one-third of the pipe 
tap taper. This makes them a little over i degree, 
nearly i}( degrees, or almost i degree and 15 minutes. 

The same makers allow a taper of y^-Q of an inch 
per foot in their hardened and ground steel mandrels. 

The Brown & Sharpe Mfg. Co. allow^ tcmTo of ^n 
inch per foot on arbors, making them j4 a thousandth 




Morse taper shanks. 



No. 


A 


B 


C 


D 


E 


T apcr in 
12 in. 


1 


99. 


-8 


.356 


.475 


1 " 

ti4 ' 


.COO 


2 


^ 1- 


21 


.556 


.700 


1 
4 


.602 


3 


3f 


Q.9_ 
<3l6 


.759 


.938 


5 
1 6 


.602 


4 


4f 


41 


.997 


1.231 


15 
3 2 


.623 


5 


6 


51 


1.446 


1.748 


5 

8 


.630 


8 


« ^ 

0"16 


8 


2.077 


2.494 


3 

4 


.626 



22 



Turning and Boring Tapers. 

below size at the small end on small sizes, and -ro\o be- 
low size at small end from ^ inch to 2 inches. 

Locomotive builders use a large number of ' ' body 
bound " taper bolts in the frames, cylinders, etc. The 
Baldwin Locomotive Works use --^q inch per foot, and 
the Pennsylvania R. R. 3^ inch per foot. These are 
turned in special lathes in which the tool travels at the 
desired angle with the centers. 



23 



DEC 24 1903 



LIBRPRY OF CONGRESS 



013 960 737 5 



<0 



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The Derry-Collard Company will send you any technical or educational book 
published, costing a dollar or more, on approval. 

Afford you the opportunity to see the goods before you take the cash out of 
your pocket. 

If the book is what you desire, send us the cash. 

If it isn't, send the book back. 

You are not asked for references, pedigree or deposits. 

You are trusted to do what's right. 

There's no gamble in this thing so far as you're concerned. 

You take no chances. 

You keep hold of your cash until vou're satisfied. 

So, if there's any technical book costing a dollar or more you care to look at 
before you buy, to be returned if not satisfactory ; or, if you are at a loss to know- 
just what books contain certain information, 

Ask us. 

We'll send vou what we believe will serve you best, you to send us the cash 
for books you keep, and return the others. 

This plan is worth trying, to say the least. 

Books are a means to a better knowledge of things, which in turn m.eans : 

Higher responsibilities, 

Higher salaries. 

Better things all around. 

We'll help you to all. 

The Derry-Collard Company 

256 Broadway, New York. City 

FRED H. COLVIN, President. 



